直流式低速风洞流动特性研究

针对新建的东北电力大学直流式低速风洞,介绍了其流场品质的测试方法和测试数据分析.包括:实验段风速、气流稳定性、流场均匀性、气流偏角、紊流度等五项,给出了测量的数值结果和相关参数的分布曲线,并确定了风机工作频率与气体流速之间的关系.     

加氢降凝组合工艺技术

抚顺石油化工研究院开发的生产低凝清洁柴油加氢降凝组合工艺,集加氢精制与临氢降凝工艺技术优点于一体,具有工艺流程简单、精制及降凝效果好、柴油收率高、原料适应能力强、产品方案灵活等特点,已在哈尔滨等炼油厂得到工业应用.     

低苯乙烯散发不饱和聚酯树脂研究

用单官能团醇对不饱和聚酯树脂改性，合成了苯乙烯质量分数为30％和W01树脂，对W01树脂的挥发性和反应性进行了测定，研究了成膜助剂对01树脂性能的影响，并与通用型191树脂和一种亚克力板层间粘合用不饱和聚酯树脂进行了比较；指出结合成膜助剂的W01树脂进一步降低苯乙烯的散发。     

Reprint of “Suppressing propylene carbonate decomposition by coating graphite electrode foil with silver”

A method has been developed to suppress the decomposition of propylene carbonate (PC) by coating graphite electrode foil with a layer of silver. Results from electrochemical impedance measurements show that the Ag-coated graphite electrode presents lower charge transfer resistance and faster diffusion of lithium ions in comparison with the virginal one. Cyclic voltammograms and discharge-charge measurements suggest that the decomposition of propylene carbonate and co-intercalation of solvated lithium ions are prevented, and lithium ions can reversibly intercalate into and deintercalate from the Ag-coated graphite electrode. These results indicate that Ag-coating is a good way to improve the electrochemical performance of graphitic carbon in PC-based electrolyte solutions.     

Synthesis of thermosetting poly(phenylene ether) containing allyl groups

New thermosetting poly(2-allyl-6-methylphenol-co-2,6-dimethylphenol)s (3) have been developed by oxidative coupling copolymerization of 2-allyl-6-methylphenol (1) with 2,6-dimethylphenol (2), followed by thermal curing. Copolymerization was conducted in nitrobenzene in the presence of copper(I) chloride and pyridine as the catalyst under a stream of oxygen, producing high molecular weight copolymers (M_n∼50,000) with broad molecular weight distributions (M_w/M_n∼35). The structure of resulting copolymers 3 was characterized by IR, ¹H, and ¹³C NMR spectroscopy. Cross-linking reactions of copolymers were carried out by thermal treatment in the absence or presence of a peroxide (3 wt%, 2,5-dimethyl-2,5-di(tert-butylperoxy)-3-butane). The 10% weight loss and glass transition temperatures of the cured copolymers were 436 °C in nitrogen and 235 °C, respectively after curing at 70 °C for 1 h and 300 °C for 1 h. The average refractive index of the cured copolymer (3b) film was 1.5407, from which the dielectric constant (ε) at 1 MHz was estimated as 2.6. The ε and dissipation factor of copolymer-films at 1 MHz were directly measured from their capacitances as 2.5-2.6 and 0.0015-0.0019, respectively.     

计量用低速风洞结构参数仿真研究

为准确分析风洞结构参数对所产生的风场稳定性的影响规律,以现有低速风洞为蓝本,通过改变其试验段结构参数建立多个不同参数试验模型;采用ansys CFD对建立的多个新模型进行结构流体仿真,对仿真结果进行数据拟合,找出风洞收缩段曲线结构参数变化对试验段轴向风速梯度和法向风速均匀性的影响;仿真实验结果表明,试验段法向中心面的有效试验区的均匀性系数随着收缩段长度增加而减小,到一定程度趋于稳定,风洞模型在L＞ 23 cm后风场均匀性系数基本处于稳定,试验段前半段的风速轴向梯度明显大于后半段的风速轴向梯度,有效试验区域多集中在后半段,风洞模型中轴向有效试验区域x＞(10～15) cm,可以为风洞的设计提供可靠参考.     

基于正交频分复用的低轨卫星移动通信同步控制系统设计

低轨卫星移动通信信息存在复用保护间隔,为实现对传输数据信息的精准定位,设计基于正交频分复用的低轨卫星移动通信同步控制系统;设置电源管理模块,初步协调BDG—MF—OS型卫星终端与ZIGBEE无线数据传输模块,将卫星通信信息反馈至网络与显示模块,实现低轨卫星移动通信同步控制系统的硬件设计;建立同步信号模型,通过信号调制解调的方式,完善待处理通信信息的复用保护间隔与循环前缀,实现正交频分复用处理的关键技术研究;分包处理通信数据,借助已知的短报文通信模式,连接同步通信协议,完成低轨卫星移动通信同步控制;与北斗型通信控制系统相比,正交频分复用技术作用下,低轨卫星的移动通信能力得到强化,较好地满足精准定位传输数据信息的实际应用需求.     

复杂山地剩余静校正方法分析

剩余静校正的精度直接影响地震资料的信噪比和分辨率、速度分析质量,进而影响成像质量。复杂山地地震资料剩余静校正计算时经常会出现局部收敛不足或者收敛于局部极值(出现"周波跳跃"现象)。研究发现,当剩余静校正量超过有效波主频周期的二分之一且波形相似时,容易出现收敛于局部极值。在完成野外静校正的基础上做好资料准备和参数选择两方面工作可以消除收敛于局部极值,达到全局收敛。     

浅谈智能变电站关键技术及其发展制约

本文对智能变电站进行了全面的介绍,对其所采用的新技术进行纵深解析,并对比了智能变电站与常规变电站之间的差异,突出智能变电站各项技术的优越性;结合智能变电站的实际运行经验,指出了新技术所存在的欠缺或发展上的制约,并提出了今后的改进方向。